The present invention relates to a stepless drive wrench for rotating a tool in one of two selectable directions. Specifically, a stepless reversible one-way wrench for rotating a socket is disclosed.
Ratchet handles are used by mechanics to rotate a socket which tightens a hex nut or hex screw. The selected socket is snapped into place over a tool holder, which is in turn rotated by a ratchet handle. The coupling between the tool holder and ratchet handle is such that one-way rotation of the tool is possible, while permitting rotation of the ratchet handle in the opposite direction in a decoupled state from the socket. The one-way coupling is effected either through a ratchet wheel and a pawl which engage the handle and tool holder, or in the case of stepless wrench, a reversible one-way clutch is provided between the ratchet handle and tool holder.
In the toothed ratchet wheel and pawl-type of ratchet handle, a larger amount of space is required to rotate the ratchet handle so that the pawl engages with the tool ratchet wheel. The present invention relates to a stepless wrench which can be used in confined spaces where the ratchet handle has a restricted rotational arc.
Stepless ratchet handles are known in the art, and are described in numerous references including U.S. Pat. Nos. 4,457,416, 4,669,339, 5,086,673, 4,457,416, and 4,051,935. Each of these devices includes a drive mechanism having a hexagonal rotator, which together with a surrounding wall delimits six peripherally tapered spaces. The tapered spaces are separated and includes therein a body, for engaging the rotator with the interior surface of the ratchet handle.
The difficulty with these prior art devices relates to the complexity of manufacture. The devices include not only a one-way drive mechanism, but a means to reverse the direction of the drive so that the wrench can be used in both a tightening and loosening operation.
The present invention is an improvement over the earlier devices, representing a simpler and inexpensively manufactured device.